Halfway between Earth and the moon, a fuel cell rupture in the Apollo 13 service module causes a massive explosion. The crew has to activate the landing module, Aquarius, to use it as a “lifeboat”; the oxygen and power reserves of the command module, Odyssey, have been compromised by the explosion and must be preserved for re-entry. The crew endures extreme cold and must ration consumables to survive. Fortunately, there’s enough fuel in Aquarius’ descent stage to put the combined vehicle on a free-return trajectory, looping it around the far side of the moon for an immediate return to Earth.
This mission is dramatized in both the We Interrupt This Mission episode of HBO’s 1998 series From The Earth To The Moon, as well as the 1995 movie Apollo 13.